Spondon FZR Genesis

[Gamma498]

Hi folks, I'm new to the forum but thought I'd join and use the wealth of expeience on here, if you don't mind! I have an '87 Genesis motor housed in a Spondon chassis and have decided to try and fit a Thunderace motor in there instead. I've had a look around a few FZR forums and views are conflicting as to whether the cylinder angle on EXUPS/ Thunderaces is different, I was under the impression that Genesis motors had cylinders at 45degrees and Exups/ Thunderaces were at 35 degrees, is this correct? One guy was adamant that they were the same and that he had put an Exup motor in a genesis chassis. Do you think I will have any problem doing the motor transplant? The frame is pretty compact and tight to the genesis motor, any advice would be much appreciated.

[kolederacer]

The angle is for the valves in the head, the cylinder is not leaned over any more at all.
I have mixed and matched all kinds of fzr1000, yzf750, and yzf1000 parts.
Sweet frame btw! How much does one of those run?

[Gamma498]

Cheers for the info, Hopefully it will be an easy conversion then, good job as I've already bought the Thunderace motor, just got to pick it up! The frame is nearly 30 years old as it was built in 1987 but back then it would have been about 3 grand and is one of only three in existence.

[kolederacer]

Also the carb boot size is larger and exhaust bolt size is larger but that is an easy fix.
Another easy add on especially for you since there are more around there is a 88 fzr750 cid, it will give you a higher redline.
Also a set of yzf750 cams. Another little trick for the higher rpms if you do that is use exhaust valve springs on the intake side also they are a little stiffer.